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Posted by admin on April 16, 2014

PDCA stands for the Plan-Do-Check-Act method that is used in many problem-solving approaches, such as A3 and 8 Dimensions (8D).   A3 refers to a European paper size template that is used for proposals, status updates and problem solving and was popularized by Toyota Motor Corporation. 8D is very popular in the auto industry and other manufacturing assembly industries that like to take a team approach to problem solving.

Let’s take a look at the basic steps of the A3 process as an example of how the PDCA method works:

  1. Identify the problem or need
  2. Understand the current situation/state
  3. Develop the goal statement (the target state)
  4. Perform root cause analysis
  5. Brainstorm/determine countermeasures
  6. Create a countermeasures implementation plan
  7. Check results – confirm the effect
  8. Update standard work


In this example, steps 1 through 5 are the ”Plan”, Step 6 is the “Do”, Step 7 is the “Check” and Step 8 is the “Act”.

One of the strengths of PDCA approaches to problem solving is that they make it is easier to document and report on problem-solving activities.  A strength of the A3 process is its flexibility in a number of situations, not just in problem solving.  This means that workers only have to learn one process and can use it in multiple situations.  This can reduce the need to learn multiple processes for very specific applications.  A strength of 8D is its focus on teamwork, with three of the eight dimensions dedicated solely to team activities. 

A shortcoming of many PDCA approaches to problem solving is that they don’t emphasize a very specific process for getting to root cause.  For example, if you look at the basic A3 steps above, “Perform root cause analysis” is relegated to one of the eight steps.  We know from our experience in helping manufacturers improve their problem-solving capabilities and systems that the root cause analysis (RCA) process is a multi-step process in its own right.  Effective RCA requires defining the problem; collecting data; narrowing possible causes; identifying the true cause of the problem; selecting the best fix; considering what could go wrong with the fix; implementing the fix; and thinking where else the problem might appear so preventive measures can be taken.

Many PDCA methods are connected to Lean manufacturing, which instantly generates a lot of interest among those focused on Lean as the savior of manufacturing.  As we have stated in prior blog posts, Lean can be a very effective management tool but too often is used to generate agreement to a certain process or approach.  “It’s part of Lean,” a proponent says, and suddenly everyone is nodding in agreement without questioning if the process or approach will meet the company’s specific needs. 

The use of PDCA and RCA doesn’t have to be an “either or” situation.  We have seen companies achieve great results when they apply PDCA and RCA in tandem.  The PDCA method, such as A3 or 8D, provides a framework for documenting and reporting problem solving activity and the RCA process provides the in-depth, rigorous process to get to root cause and implement the right fix.  This can be a powerful combination in addressing problems, especially those lingering and recurring problems that seem unsolvable.